how to build a 1mhz oscillator...?

Question by iliashassim 7 years ago  |  last reply 6 years ago


What are capacitors for in oscillator circuit for pic?

I've been learning to program pic18f1320 with led blinker program and using 10Mhz oscillator. I don't have right capacitors but circuit works without them just fine... 

Question by bratan 7 years ago  |  last reply 7 years ago


Where I can find resistors, capasitors, LEDs and tranistors cheap?

Question by zacenergy 10 years ago  |  last reply 6 years ago


A samsung TV LE40R86BD after changing the capasitors still flashing .What to do ?

I have a samsung TV LE40R86BD which have no start only flashing.I tried as discribed on your home page and chage the four capasitors but it still flashing (the capasitors were defective)?

Question by rehadi 6 years ago  |  last reply 6 years ago


i just took apart a capasitor and theres a few meters of metal sheet, what is it? Answered

I just took apart a 250microfarad capasitor i got out of a old tv, and when i opened it up, there was a long coiled sheet of metal sheet, and i would like to ask, what is this metal comprised of? wikipedia has been no help, nor has google whoever answers this will get  a best answer from me

Question by oldmanbeefjerky 8 years ago  |  last reply 8 years ago


which capasitors and resistors shold i use to convert 12v to 3v and again to 12v for rc circuit

Please answer me as soon asa possible!

Question by Aditya SinghG 2 years ago  |  last reply 2 years ago


is there a way to make an ac arc using a disposable camera? Answered

I am currently searching for a way to mod a disposable camera so it will make an ac current and in extension an arc (continious or regularily pulsing , either one is fine) for my potato launchers ignition. i have seen that a decent spark can be made by connecting to wires together connected to the capasitor, but i want it to work electronicaly , not manualy aka with a trigger what i want to know is how (if its possible) to create an arc from the disposable caremas transformer that will work straight away, or converted from the capasitors dicharge into ac current which can jump to cause ignition.

Question by oldmanbeefjerky 8 years ago  |  last reply 7 years ago


No volume in Fisher RS-280 synthesizer receiver.Everything else seems to work.Is there a fix like fuse or capasitor?

I havn't opened up receiver yet I need some information first.I get no sound from receiver at all.I started out by connecting all components such as CD player but have since removed all accessories,i'm down to just the receiver and speakers.Is there something I should look for when I open the receiver up?This is a very nice vintage receiver and I would like to use as primary receiver.Could it be something as easy as a fuse? I opened the stereo and found that 2 fuses are missing they are located on the main board at  F401 & F402 both are T2A fuses I believe.are these fuses used for sound and should I install them anyway

Question by jimf123 1 year ago  |  last reply 1 year ago


how do i build a voltage multiplier for changing 6 volts to 12 volts using diodes and capasitors?

Hi, since my last question failed miserable resulting in me wasting a bunch of good dollars on a useless , and at the time what was described as a "voltage multiplier", uln2003an darlington transitor array which doent seem to do anything like i was told, i am going oldschool and building a voltage multiplier so i can switch a 12v relay card from here, to power 2 motors via remote control using a 9 amp 12 volt current (10 bats X 1.2v X 3A )X 3 sets in paralell , for my r/c tank which i have used a receiver from a toy car which i have increased its remote control signal to up to 100m away (its a 40mhz remote from china nothing special). anyway i am trying to aquire a 12 volt current ( any amperage above what seems to be less that 5 ma according to the relay cards description) from my receiver that gives me 6 volts 700ma from the motor and 4 volts 900ma for the servo. recently i lost a diode for one of the 4 relay cards i am using so i sent my mother to buy me a uln2003an from jaycar and a single 1n4148 diode from jaycar as well, somehow she was tricked into buying a 100 bulk pack (wich she payed twice for despite getting only 1 bulk pack) but did get me the diode i needed for the relay to work without blowing the "on " led rendeing the relay for somereason inoperable. i have 99 1n4148 diodes now and i want to know if i can make these into a voltage multiplier for the relay to get turned on at 12 volts, using capasitors as well, i know it can be doen, i just dont know what kind of capastor to use or how to assemble it once i have the capasitor. please help em i have een stuck with this for ages and the answer is no i dont know how to use a transistor to switch the relay all i see is 4 ports 12v in 12 v out (for switching relay on) and the switcing part wich is conected to relay contacts http://www.jaycar.com.au/productView.asp?ID=ZR1105&keywords;=1n4148&form;=KEYWORD http://www.jaycar.com.au/productView.asp?ID=KC5434&keywords;=relay+kit&form;=KEYWORD links to the diodes i have and the relay ard also heres the transistor i have http://www.jaycar.com.au/productView.asp?ID=ZK8855&keywords;=uln2003&form;=KEYWORD despite description it says uln2003an on the chip

Question by oldmanbeefjerky 8 years ago  |  last reply 8 years ago


is it possible to make lightning gloves?

A friend of mine is offering me big bucks if i build him  a pair of lightning gloves which would shoot large sparks or lightning from one glove to the other. now because ive never built a voltage multiplier befor ei would like to know if theres any problems with my idea which is i get a  small 12v battery pack for racing car i connect that bttery (with a resistor ) to a transformer i then make a voltage multiplier with hv capasitors and diodes to multiply the voltage until a certain voltage is obtained. however i do not know how hoigh the voltage should be so that it is not lethal, but can jump at least one meter from one glove to the other. also as a safety precaution a large copper wire suit should be worn which me and my friend used on my uncles high voltage vandegraf generator whish shot 20m lighnting at us in our loighting suits ontop of our diving suits , and we never felt a thing. anyways, can you please tell e the specs of everything i will need to acomplish my mission?

Question by oldmanbeefjerky 8 years ago  |  last reply 8 years ago


Why Cordless Drill (Bosch 7,2volt) do not work using Laptop Adapter

Hello all.. I got problem with my cordless drill. It's battery is leak and i need to replace it using Laptop Adapter power suply. I have HP laptop adapter with Voltage Output 18,5Volt 3.8Amp. I just connected the + and - of laptop adapter to the cordless drill, BUT it do not want to turn and ONLY MOVE SEQUENCE (move-stop-move-stop-move-stop....). Its move is so strange for me, it's like pulse voltage because the drill just move for a moment then its stop, then its move and stop and always like that... I don't know is it DC or AC, and I've try to make circuit to make its voltage become DC using 4 diode and capasitor, But the result is same (move-stop-move-stop...). Then, I try to connecting the cable adapter to the drill and then pull off and connecting again with rapid sequence. Then the drill want to turn fastly... Please Help me, how to solve this, i need this adapter work for my cordless drill.... I've make a test to, I used AC dinamo (not DC dinamo motor) and connect it with the Laptop adapter, it's turn normally and fast... Please anyone here help me...

Topic by ddeeen 5 years ago  |  last reply 1 year ago


Reefing it with LED's (help needed)

Well this is my second post and I am a bit more learned in the ways of LED circuits from many of your posts. Objective: Create a high light output LED array that will peak at around 16,000K for growing coral for reef aquariums.Primary strategy: connect 10 or more Luxeon III stars in seriesPreferred requirements: Energy efficient, Low Heat emittance, Needs to peak out at the appropriate spectrum for the coral ( I have that covered just by changing the ratio of cool whites to royal blue Luxeon III's)At the moment I a just going for a simple on/off, later i would like to employ a form of automated dimming so that it fades on and off so there is not such a sharp on off with the LED's. So far I have a circuit that i plan on modeling my LED array after since it was readily available for me to dissect. The following is an LED array. I know that there is a diode rectifier bridge built in there and a smoothing capasitor but there are to components i do not recognize they are connected at the positive and negative ends of the circuit. One is the Yellow (doohickey with part # 684j 250) component attached to the positive lead and the other is a clear (fuse/resistor hybrid) component next to the resistor on the board.https://www.instructables.com/files/deriv/FGX/D7E2/FBQ33XYA/FGXD7E2FBQ33XYA.MEDIUM.jpghttps://www.instructables.com/files/deriv/FGX/D7E2/FBQ33XYA/FGXD7E2FBQ33XYA.MEDIUM.jpgI was able to draw the circuit and it seems pretty straight forward but I just need to know if I will be able to spec the appropriate components to operate 10 leds in series (Each LED operates with a Vf=3.9 V and I= 1000mA ) they will need a supply of more then 40V DC.Any help or dialogue I can get the more the better and the more I will learn In addition I looked at Dan's high power constant current but not sure how well it would operate under the conditions that I have specifiedPrimary LED's in use for the Reef light: (note all are stars)LED part # Color Type Vf Amps Lux LXHL-LW3C cool white Lambertian 3.9 1000mA 80lumensLXHL-LR3C Royal blue Lambertian 3.9 1000mA 445mWLumensLXHL-MW1D cool white " " 3.42 350 mA 45 LumensLXHL-MRRD Royal Blue "" "" 3.42 350 mA 220 mWLumensThere was little to no difference between the 700 mA series and the 1000mA series so I did not list themI look forward to all your helpTom

Topic by Aquatope 11 years ago  |  last reply 11 years ago


Reefer meets High Power LEDs (looking for help)

Well this is my second post and I am a bit more learned in the ways of LED circuits from many of your posts.Objective: Create a high light output LED array that will peak at around 16,000K for growing coral for reef aquariums.Primary strategy: connect 10 or more Luxeon III stars in seriesPreferred requirements: Energy efficient, Low Heat emittance, Needs to peak out at the appropriate spectrum for the coral ( I have that covered just by changing the ratio of cool whites to royal blue Luxeon III's)At the moment I a just going for a simple on/off, later i would like to employ a form of automated dimming so that it fades on and off so there is not such a sharp on off with the LED's. So far I have a circuit that i plan on modeling my LED array after since it was readily available for me to dissect. The following is an LED array. I know that there is a diode rectifier bridge built in there and a smoothing capasitor but there are to components i do not recognize they are connected at the positive and negative ends of the circuit. One is the Yellow (doohickey with part # 684j 250) component attached to the positive lead and the other is a clear (fuse/resistor hybrid) component next to the resistor on the board.https://www.instructables.com/files/deriv/FGX/D7E2/FBQ33XYA/FGXD7E2FBQ33XYA.MEDIUM.jpghttps://www.instructables.com/files/deriv/FGX/D7E2/FBQ33XYA/FGXD7E2FBQ33XYA.MEDIUM.jpgI was able to draw the circuit and it seems pretty straight forward but I just need to know if I will be able to spec the appropriate components to operate 10 leds in series (Each LED operates with a Vf=3.9 V and I= 1000mA ) they will need a supply of more then 40V DC.Any help or dialogue I can get the more the better and the more I will learnIn addition I looked at Dan's high power constant current but not sure how well it would operate under the conditions that I have specifiedPrimary LED's in use for the Reef light: (note all are stars)LED part # Color Type Vf Amps LuxLXHL-LW3C cool white Lambertian 3.9 1000mA 80lumensLXHL-LR3C Royal blue Lambertian 3.9 1000mA 445mWLumensLXHL-MW1D cool white " " 3.42 350 mA 45 LumensLXHL-MRRD Royal Blue "" "" 3.42 350 mA 220 mWLumensThere was little to no difference between the 700 mA series and the 1000mA series so I did not list themI look forward to all your helpTom

Topic by Aquatope 11 years ago